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Sept. 24, 1963 M. I =LAUT ADDING MACHINES 2 Sheets-Sheet 1 Filed Dec. 21, 1960 w l l m hm 4 7 ra /raw Sept. 24, 1963 2 Sheets-Sheet 2 Filed Dec. 21, 1960 ifs-.5.-

United States Patent 3,104,807 ADDING MACHHJES Michael Plant, Zahala, Tel Aviv, Israel 1 (R0. Box 26, Rehovoth, lsraei) Filed Dec. 21, 1966, Scr. No. 77,437 Claims priority, application Esraei inn. 4, 196%) 1 Claim. (Cl. 23 5-6tl) This invention relates to adding machines and in particular to the control mechanism of these machines.

The term adding machines is known in the trade to designate those machines by which the following operations can be performed: adding, subtracting, totalling and subtotalling, multiplication, and the printing of numbers which are not added.

In the known machine there is generally provided for each of these operations a separate machine part which governs the process of the particular operation only. This means that the know machines have to comprise many parts which must be manufactured and assembled, and maintained when the adding machine is in use. Thus the cost of both the manufacture and the maintenance of the known adding machines is very high.

It is the object of the present invention to lower the cost of manufacture of an adding machine by providing a single control mechanism for the control of all the abovementioned operations.

The invention consists in an adding machine having an operation control mechanism comprising a single movable controlling element having a series of steps along one edge which steps cooperate with a pin to govern the operations to be performed; a cam slot for starting the operation of the motor control; a cam slot for controlling the register lock; a cam step for locking the transfer members; and a cam step for freeing the adding bars.

. In a preferred embodiment of the invention the pin is mounted on one member of an operation control linkage governed by function selecting keys.

In a further preferred embodiment of the invention the controlling element is constituted by an elongated control bar mounted for reciprocal longitudinal forward and return movement along one side of the machine, a spring urging the bar into its forward operating position, the steps being coordinated to the cam slot.

The invention is illustrated, by way of example only, in the accompanying drawings, in which:

FIG. 1 shows an elevation as seen from the right of a mounted control bar with its associated mechanisms.

FIG. 2 shows a perspective view of the control linkage and the operating keys.

The adding machine according to the invention comprises a right assembly plate 2 and a left assembly plate (not shown) between which plates the adding mechanism of the machine is disposed as described in my co-pending patent application No. 77,438 filed December 21, 1960, and entitled Adding Machines.

The control bar 11 is mounted at an angle along the right assembly plate 2 for reciprocal longitudinal forward and backward movement between two rollers 12a and 12b fixed to the assembly plate 2 near the hack of the machine and a pin 13 fixed to the assembly plate and extending in an elongated guiding slot lib in the front part of the control bar. A spring 14, attached with one end to the fixed axis of the roller 1 2a and with its other end to the front end of the control bar 11, urges the latter forward 7 into its operating position, i.e. to the back of the machine.

The lower edge of the control bar is cut into steps 11c constituting a cam, each step representing a different operation of the machine. A pin 27a on the operations control linkageto be hereinafter describedengages the step cam and provides the stop for it, determining thereby the relative forward position to which the control bar can 'ice be pulled by the spring 14. An elongated cam slot 11a coordinated to the step-cam is provided in the back of the control bar 11 and has a follower pin 63b extending through it. The pin 63b is fixed to operating means (not shown) described and claimed in my co-pending U.S. patent application No. 77,438 filed December 21, 1960, and entitled Adding Machines to determine, according to the forward position of the control bar 11, their correct operating position for the desired calculating operation. The back edge 11b of the slot 11b is slightly enlarged upwardly, a pin 31a of the motor control lever, to be hereinafter described extending into this enlarged portion 11b.

The means for returning the control bar 11 into its starting position after .a calculating cycle has been completed comprise a lever 17 whose upper end is provided with a roller 17a abutting against the rear edge of the bar 11, and whose lower end is fixed to a plate 18 and is swingable with it, being pivoted in the right assembly plate. The upper edge of the plate 18 has a cam surface 18a which is engaged by a follower on an operating cam rotating on the main control axis 62 and which at the end of an operation cycle is actuated by the follower to make the lever push the bar 11 back into its starting position.

The control bar 11 is integral with several other control means as follows: on its upper edge two cam steps are provided. The back one, cam step 110., actuates means for suppressing the movement of ten-transfer members when a total operation is to be made as described in my aforementioned co-pending US. patent application No. 77,438. These means comprise a pin 20a adapted to engage the cam step 11d, the pin 20a extending outwardly from the front edge of the lateral leg of an L-shaped lever 20 which is arranged on the outside of the right as sembly plate by being pivotable on an axis 21 extending at the corner of the L through both right and left assembly plates. To the top of the upright leg of the L-lever a bar 19 is fixed, which bar is moved backwards, i.e. towards the front of the machine, to control the movement of said ten-transfer members.

The front cam step lle actuates the means for releasing one of the locking means of said adding mechanism as de cribed in my aforementioned co-pending US. patent application No. 77,438. These means comprise a pin 22a adapted to engage cam step He, the pin 22a extending outwardly from substantially the center of a straight lever 22 whose back end is pivotally arranged on axis 21 and whose front end carries a short inwardly extending rod 2212 which is adapted to lift said locking means from below. To the inside surface of the bar below the slot 11 an angle-shaped lug 15 is fixed. This lug is destined to push over a pin 59 on the operating means when a subtotal or total registering operation is to be performed as described in my aforementioned co-pending U.S. application No. 77,438. An abutment l6 behind and below the lug 15 on the inside surface of the bar serves for pulling said pin back to its starting position.

The control bar carries further the printing symbols to indicate which operation is being performed. These symbols 23 are integral with one leg of a U-shaped bridge member 24 whose web straddles the assembly plate 2, while the other leg, parallel to the first one, is fixed to the rear end of the control bar 11. Owing to the forward movement of the control bar to a particular cam step 110 according to the operation being performed, the symbol indicating the particular operation is brought into alignment with the members of the adding mechanism to be printed together with them.

The signals of the various operations are transmitted from the keyboard (to be hereinafter described) to the control bar 11 by means of the operations control linkage. It comprises essentially a 3-bar linkage constituted by an upper link 25' extending longitudinally on the outside of the tiplication.

right assembly plate 2 and pivoted with its front end on an axle 28 extending between the right and left assembly plates and projecting from the latter. The link 25 carries on its underside a pin 25a which extends normal thereto at the left and right having the underside of the operation key levers bear thereon. The other end of link 25 is pivotally connected to the upper end of a vertically extending link 26 whose lower end is pivotally connected to one end of a link 27 extending longitudinally substantially parallel to the link 25. The other end of link 27 is pivoted on an axle 29 turnably mounted between the left and right assembly plates. The link 27 carries the pin 27a which extends inwardly to engage the cam steps 110 of the main control bar 11 as hereinbefore described. The depth to which the link 27 and thus the pin 27a is depressed by the links 25 and 26 governs the position'of the pin 27a relative to the main control bar lL'sincewhen the latter is free to move it is always urged by the spring 14 into its forward position and against pin 27a.

To the axle 29 a motor starting lever 30' is movably fixed. The lever 30 extends along the outside of the right assembly plate and is loosely held in a bracket 3%. It carries at its free end an upwardly extending locking tooth 3% which, when the machine is not operating, engages the motor cam fixed to the main control shaft levers SZct-except the one associated with the multiplication operation, are pivotally arranged on axle 28, the lever 32a of the multiplication key being fixed to said axle.

The lower edges of the levers 3-26 are adapted to abut the pin a of link 25 to depress the latter, the depth of which it is depressed depending on stops 32b, constituted by projections, provided at a difierent height on the side of each key 32 and abutting the top of plate 33- when the keys are depressed. The key associated with total and When the plate 34 is at the right side of the machine, the

62. The lever 39 has fixed to a point substantially mid- 7 way between its end an upwardly extending bar 31 carrying pin 31a which is in the inoperative position of the main control bar 11 extends into the enlarged portion 11b of the guiding slot 11b. To the left end of axle 29 a trip lever of the motor startingswitch (not shown) is fixed, the motor itself being mounted at the back of the machine between the assembly plates. When the pin 27a is depressed during the forward movement of the control bar 11, the pin 31a is pushed downwards as it moves from the portion 11b of the slot 11b into the slot itself.

This small downward movement moves the lever 3%] like-' wise downward, which on the one hand causes the tooth 39a to disengage from the cam and on the other hand causes the axle 29 to turn slightly, thereby actuating'the starting switch of the motor and starting the latter which in turn starts the rotation of the main control shaft 62 with its cams.

There are four function controllingkeys, as follows: one key for adding and total; one key for subtracting and subtotal; one key for non-adding; and one key for mul- The keys 32 are constituted by uprightly extending bars to the top of which the buttons indicating the operation are fixed, as known per se. The keys 32 are guided in a plate 33 fixed between the left and right assembly plates. The bottom of keys 32 extend below plate 33 and are fixed to longitudinally extending levers 32a, two of which are arranged on either side of the link 25, springs 32 being attachedwith one end to the levers 32a and with the other end to the plate 313, to return the keys 32 to their position of rest. The front ends of all the bars 320 clear it when the keys 32 are depressed by extending through a notch in the plate 34, the limitation of the depression of these keys being the stops 32b in this case. Thus it can be seen that the link 25 and thus link 27 with its pin 2741 can be depressed to six different depths corresponding to the six possible operations, so that by the engagement of the pin 27a: with the six different cam steps of the control bar, six operating positions of the latter are achieved.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:

An adding machine having functional selecting keys, the operation control mechanism comprising a motor, a pin, a single movable, controlling element having a series of steps along one edge, which steps cooperate with said pin to govern the operations to be performed, a cam slot for starting the operation of said motor, a register lock, transfer member, a cam step for locking said transfer members, adding bars, a cam step for freeing said adding bars,'an operation control linkage, said pin being mounted on said operation control linkage and governed by said function selecting keys, said control linkage comprising a three-bar linkage, mounted adjacent said control linkage, the upper link extending longitudinally, the middle linkage being substantially at right angles and the lower linkage lower linkage carrying said pin. 7

being substantially parallel to said upper linkage and said References Cited 'in thefile of this patent UNITED STATES PATENTS 

